Clients understandably want certainty before they commit to construction.
If a project is forecast to cost £5m, the leadership team needs confidence that the figure is not simply the best estimate available at the time, but a number that has been tested against the design, the building, the market and the remaining risks.
At EthosEQ, one of the commitments we make is to target 95% cost certainty before construction starts.
That does not mean pretending there is no uncertainty. It means progressively reducing uncertainty through the life of the project until the residual risk is understood, quantified and managed.
The 95% is therefore not created at the end of the process.
It is built up through a series of decisions, investigations and commercial controls from the very beginning.
Cost certainty starts with scope certainty
The first requirement is a clear understanding of what is actually being delivered.
A cost plan can only be as reliable as the scope it is based on. If the client is still deciding headcount, workplace standards, catering provision, AV strategy, meeting-room ratios or the extent of reuse, then the budget is still exposed to scope change.
That does not mean the project needs to be fully designed before meaningful cost advice can be given. It means the assumptions need to be clear and the major cost drivers need to be understood.
Good cost planning therefore starts by defining the scope, identifying the decisions that could materially affect it and making those decisions visible.
As the brief becomes clearer, one of the biggest sources of uncertainty starts to fall away.
Surveys reduce building risk
The second requirement is understanding the building.
Existing offices can contain significant unknowns around MEP capacity, plant condition, fire stopping, asbestos, structure, power, drainage and landlord interfaces.
These risks are often where early budgets are most vulnerable.
The response should not simply be to add a larger contingency.
The better approach is to investigate them.
Where appropriate surveys can remove uncertainty, they should be carried out early enough to influence design and procurement.
A relatively small amount spent on due diligence can prevent a much larger financial surprise during construction.
This is one of the clearest ways in which cost confidence improves: assumptions are progressively replaced with evidence.
Risk should be identified, not hidden
The third requirement is active risk management.
A generic contingency percentage can provide a useful starting allowance, but it does not create certainty by itself.
We prefer to identify specific risks, assess their likelihood and impact, allocate ownership and then determine how each risk should be managed.
Some risks can be removed through design development. Some can be reduced through further investigation. Others can be transferred contractually, while some remain with the client and need an appropriate financial allowance.
The important point is that the budget should explain why risk money is being held.
As risks are closed out, the allowance should reduce.
That is how contingency becomes a managed number rather than a permanent buffer.
Design development reduces estimating uncertainty
Another part of the process is improving the quality of the design information.
Early estimates inevitably rely more heavily on benchmarks and assumptions. As the design develops, quantities become measurable, specifications become clearer and the number of unknowns falls.
That allows the cost plan to move from a broad forecast towards a much more detailed and evidence-based position.
But design development alone is not enough.
The key is to make sure the important commercial decisions are being resolved at the same time.
There is little value in producing more detailed drawings if the major cost drivers remain undecided.
Market testing reduces pricing risk
An estimate becomes more reliable when it is tested against the market.
Recent benchmarks and historic data are useful, but contractor and subcontractor pricing provides a stronger level of evidence.
Depending on the procurement route, this may happen through early package testing, subcontractor engagement, two-stage procurement or a full competitive tender.
The purpose is to replace estimated rates with live market information wherever practical before construction begins.
That is one of the biggest steps towards genuine cost certainty.
Procurement has to support the target
The procurement route also matters.
A single-stage tender can provide strong price competition where the design is sufficiently complete.
A two-stage route can improve buildability, programme certainty and early market engagement, but only if the PCSA is properly managed and package pricing is progressively tested.
The route itself does not create certainty.
The commercial controls around it do.
If major packages remain untested, design responsibilities are unclear or contractor allowances are still provisional, the project cannot realistically claim the same level of confidence as one where those issues have been resolved.
That is why procurement strategy should be linked directly to the cost-certainty target.
Assumptions should progressively disappear
Every early cost plan contains assumptions.
That is entirely normal.
The important thing is that assumptions are recorded, visible and actively managed.
For example, a project might initially assume that existing cooling capacity is sufficient, that no structural strengthening is required or that construction can proceed during normal working hours.
Those assumptions should not still be sitting unresolved immediately before construction.
By that stage, they should either have been confirmed, replaced with better information or converted into a clearly identified residual risk.
The closer the project gets to construction, the fewer significant assumptions should remain.
That is another important test of confidence.
The total project budget needs the same discipline
Cost certainty should not apply only to the construction contract.
For occupiers, the total capital requirement can also include fees, surveys, furniture, IT, AV, security, move costs, landlord interfaces, inflation and client-held risk.
If those items are not included or clearly separated, the construction cost may be accurate while the overall investment decision is still wrong.
A 95% confidence target therefore needs to apply to the whole project budget, not just the contractor’s number.
How risk is progressively reduced
The simplest way to think about this is that cost certainty should improve as the project moves through a series of gateways.
At the beginning, there is more uncertainty around scope, building condition, design, procurement and market pricing.
As the project develops, those uncertainties should be deliberately reduced.
Scope becomes clearer. Surveys replace assumptions. Design becomes measurable. Risks are identified and closed out. The market is tested. Procurement decisions are made. Contractor pricing becomes firmer. Remaining allowances are understood.
By the time construction starts, the objective is that the client is no longer relying on a large number of untested assumptions.
The remaining risk should be relatively small, visible and manageable.
That is what makes a 95% cost-certainty target credible.
Final thought
I do not think cost certainty is something that appears at the end of a project because somebody has produced a detailed tender report.
It is created much earlier.
Every survey completed, every key decision made, every risk closed out and every package market-tested removes another layer of uncertainty.
That is why early involvement matters so much.
If the cost consultant is brought in late, there is only so much risk that can be removed before construction starts.
If they are involved from the beginning, there is an opportunity to shape the brief, test options, identify abnormal costs, influence procurement and manage risk before those issues become expensive.
For me, 95% cost certainty is not about claiming that projects are predictable.
It is about having a disciplined process that makes them progressively more predictable.
The closer we get to construction, the fewer surprises there should be.
How we help
At EthosEQ, we help clients improve cost confidence by identifying the main assumptions and risks that could move the budget, then working with the project team to reduce them as the design develops.
That might mean better surveys, clearer scope, earlier decisions, market testing or a procurement route that gives the right level of price certainty.
The aim is simple: by the time construction starts, the major unknowns should have been resolved and the remaining risks should be understood.
Links
Cost Certainty Report – Expert Cost Consultancy
RICS NRM: New Rules of Measurement
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Disclaimer This article is provided for general information only and does not constitute cost, contractual, procurement, legal or investment advice. Cost certainty will vary depending on project scope, design maturity, available surveys, market conditions, procurement strategy and the level of residual risk. The 95% cost-certainty target referred to in this article reflects EthosEQ’s approach to managing and reducing uncertainty before construction and should not be interpreted as a guarantee that project costs cannot change. Project-specific professional advice should always be obtained.
